Last week saw a flagrant attack on civil liberty mounted in the name of peace. A man who likes to walk around with a rucksack was told that he may have to spend the rest of his life in prison.

The rucksack, in this case, was not the cause of this draconian warning. It contained no bombs, real or fake. The problem was what the man, Stephen Gough, wore underneath the backpack: nothing.

Gough is better known as the Naked Rambler, an ex-marine who has spent most of the past seven years trekking around the countryside in nothing more than a pair of hiking boots and a hat. The rest of that time he has spent in police stations, courts and prisons. He has been arrested on more than 20 occasions, nearly every time in Scotland.

Just before Christmas, he was released from Perth prison, having completed his second 12-month sentence for breaching the peace. The temperature was below zero and snow was on the ground. In the circumstances, anyone looking to take offence would have had need of a microscope.

It's believed that the policemen waiting for Gough outside the prison had no such equipment. Nevertheless, he was immediately rearrested.

It may come as a surprise to anyone who's spent a Saturday night in Glasgow, Edinburgh or any other British city to learn that Scotland's moral constitution is so delicate that it requires such zealous protection from the sight of Gough's frozen genitalia. In an age when underpants can be rigged with explosives, what peace does the pantless Gough breach?

Of course, the kind of people who carry incendiary devices in their underwear would have little time for the Naked Rambler. In the unlikely event that al-Qaida ever gained power, they'd come down on him like a ton of bricks. Literally. And that should give us pause for thought, because as things stand there's not nearly enough distance on this matter between the Scottish authorities and a bunch of religious fanatics.

What is it about Britain and nudity? Even in saunas we hold on to towels as though they were lifelines. Yet bare breasts are the wallpaper of tabloid culture, lap-dancing bars litter the nation's high streets and the most forensic pornography is available at the click of a mouse.

It's as though we can only accept nudity if it's sexualised. Nudity for nudity's sake – well, that's deeply suspect. One commentator on radio suggested that children needed to be protected because Gough could be a paedophile, as though clothes were confirmation of a healthy sexuality.

Gough's behaviour is obviously unusual. But abnormal is not the same thing as criminal. While he has been adjudged to have broken the law, it's hard to see what crime he has committed. Any society that thinks prison is the correct place for him has lost grip of a basic principle of liberty. "Man is born free," wrote Rousseau, "but everywhere he is in chains."

In his own eccentric way, Stephen Gough has been trying to break those chains. He may be wrong, he may be misguided, but he's not evil. In treating him as though he were, the Scottish authorities have got their knickers in a twist. And that will prove far more damaging than not wearing any knickers at all.